Portal:Energy
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The Energy Portal Welcome to Wikipedia's Energy portal, your gateway to energy. This portal is aimed at giving you access to all energy related topics in all of its forms.
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Introduction
In physics, energy (from Ancient Greek ἐνέργεια (enérgeia) 'activity') is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J).
Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy.
Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy.
Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The Earth's climate and ecosystems processes are driven by the energy the planet receives from the Sun (although a small amount is also contributed by geothermal energy). (Full article...)
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Solar power, also known as solar electricity, is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Solar panels use the photovoltaic effect to convert light into an electric current. Concentrated solar power systems use lenses or mirrors and solar tracking systems to focus a large area of sunlight to a hot spot, often to drive a steam turbine.
In 2023, solar power systems generated 5% of the world's electricity, compared to 1% in 2015, when the Paris Agreement to limit climate change was signed. Along with onshore wind, in most countries, the cheapest levelised cost of electricity for new installations is utility-scale solar. (Full article...)
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Photo credit: Charliebrown7034
Skyglow over New York City, one form of light pollution.
Did you know?
- If atmospheric greenhouse gas concentrations can be stabilized at 450 ppm, it is thought that there will be a 50% chance of avoiding dangerous climate change?
- The Itaipu hydroelectric power plant is currently the second largest power plant in the world, supplying over 90% of Paraguay's electricity, and 25% of Brazil's?
- Libya's Sirte Basin—which in some places lies more than 47 metres below sea level—contains roughly 80% of the country's known crude oil reserves?
- Approximately 95% of the electricity consumed by a normal incandescent light bulb (example pictured) is emitted as heat, rather than as visible light?
- Saudi Aramco is the largest oil corporation in the world and the world's largest in terms of proven crude oil reserves and production?
- Newcastle, Australia, is the world's largest coal export port?
- Surplus income from oil production in Norway is invested by the Government Pension Fund, one of the World's largest funds with a value of around US$ 800 billion?
- Energy superpowers Russia and Venezuela have, respectively, the world's largest reserves of natural gas and petroleum?
Selected biography
In 1831, Faraday began his great series of experiments in which he discovered electromagnetic induction. He established that a changing magnetic field produces an electric field, a relation mathematically modelled by Faraday's law. Faraday later used the principle to construct the electric dynamo, the ancestor of modern power generators. He went on to investigate the fundamental nature of electricity, concluding in 1839 that, contrary to opinions at the time, only a single "electricity" exists, and the changing values of quantity and intensity (voltage and charge) would produce different groups of phenomena.
Some historians refer to Faraday as the best experimentalist in the history of science. Despite this his mathematical ability did not extend so far as trigonometry or any but the simplest algebra. He nevertheless possessed the ability to present his ideas in clear and simple language. During his lifetime, Faraday rejected a knighthood and twice refused to become President of the Royal Society.
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Quotations
- "The world's second-largest emitter of greenhouse gases is China. Yet, China was entirely exempted from the requirements of the Kyoto Protocol. India and Germany are among the top emitters. Yet, India was also exempt from Kyoto." – George W. Bush, 2001
- "The newly industrialized States cannot, for example, be asked to apply restrictive environmental standards to their emerging industries unless the industrialized States first apply them within their own boundaries." – Pope John Paul II, 1990
- "We should work together to make sure the international community upholds the goals and framework established in the United Nations Framework Convention on Climate Change and its Kyoto Protocol and the principle of common but differentiated responsibilities." – Hu Jintao, 2007
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